[PATCH 1/3] s390: uv: UV feature check utility

Steffen Eiden
2023-07-27T12:21:04Z

Introduces a function to check the existence of an UV feature.
Refactor feature bit checks to use the new function.

Signed-off-by: Steffen Eiden <seiden@linux.ibm.com>
---
arch/s390/include/asm/uv.h | 5 +++++
arch/s390/kernel/uv.c | 2 +-
arch/s390/kvm/kvm-s390.c | 2 +-
arch/s390/mm/fault.c | 2 +-
4 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/arch/s390/include/asm/uv.h b/arch/s390/include/asm/uv.h
index d6bb2f4f78d1..338845402324 100644
--- a/arch/s390/include/asm/uv.h
+++ b/arch/s390/include/asm/uv.h
@@ -397,6 +397,11 @@ struct uv_info {

extern struct uv_info uv_info;

+static inline bool uv_has_feature(u8 feature_bit)
+{
+ return test_bit_inv(feature_bit, &uv_info.uv_feature_indications);
+}
+
#ifdef CONFIG_PROTECTED_VIRTUALIZATION_GUEST
extern int prot_virt_guest;

diff --git a/arch/s390/kernel/uv.c b/arch/s390/kernel/uv.c
index d8b25cda5471..c82a667d2113 100644
--- a/arch/s390/kernel/uv.c
+++ b/arch/s390/kernel/uv.c
@@ -249,7 +249,7 @@ static bool should_export_before_import(struct uv_cb_header *uvcb, struct mm_str
* shared page from a different protected VM will automatically also
* transfer its ownership.
*/
- if (test_bit_inv(BIT_UV_FEAT_MISC, &uv_info.uv_feature_indications))
+ if (uv_has_feature(BIT_UV_FEAT_MISC))
return false;
if (uvcb->cmd == UVC_CMD_UNPIN_PAGE_SHARED)
return false;
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 17b81659cdb2..339e3190f6dc 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -2402,7 +2402,7 @@ static int kvm_s390_cpus_to_pv(struct kvm *kvm, u16 *rc, u16 *rrc)
struct kvm_vcpu *vcpu;

/* Disable the GISA if the ultravisor does not support AIV. */
- if (!test_bit_inv(BIT_UV_FEAT_AIV, &uv_info.uv_feature_indications))
+ if (!uv_has_feature(BIT_UV_FEAT_AIV))
kvm_s390_gisa_disable(kvm);

kvm_for_each_vcpu(i, vcpu, kvm) {
diff --git a/arch/s390/mm/fault.c b/arch/s390/mm/fault.c
index b65144c392b0..b8ef42fac2c4 100644
--- a/arch/s390/mm/fault.c
+++ b/arch/s390/mm/fault.c
@@ -824,7 +824,7 @@ void do_secure_storage_access(struct pt_regs *regs)
* reliable without the misc UV feature so we need to check
* for that as well.
*/
- if (test_bit_inv(BIT_UV_FEAT_MISC, &uv_info.uv_feature_indications) &&
+ if (uv_has_feature(BIT_UV_FEAT_MISC) &&
!test_bit_inv(61, &regs->int_parm_long)) {
/*
* When this happens, userspace did something that it
--
2.40.1